[Determination of Bioactive Components in Paeonia lactiflora Roots Cultivated in Various Areas by UHPLC].

Objective: To assess the quality of Paeonia lactiflora roots by the multi-bioactive chemical markers. Methods: Total of66 Paeonia lactiflora roots samples were collected from Sichuan,Zhejiang and Anhui. An UHPLC-DAD technique was employed to quantify the contents of paeoniflorin,hydroypaeoniflorin,abiflorin,pentagalloyglucose,benzoypaeoni-florin,paeonol,gallic and catechin in these samples. These chemical components in each sample were also calculated by Principal Component Analysis( PCA). Results: The eight bioactive components were good separated in 30 min on the UHPLC chromatogram. The correlation coefficients between peak areas and concentration for these bioactive components were not less than 0. 9990( n = 6). And their recoveries were in the range of95. 94% ~ 100. 92%( n = 6). The contents of paeoniflorin in Paeonia lactiflora roots samples collected from Sichuan,Zhejiang and Anhui were 40. 54 mg / g( n = 23),33. 09 mg / g( n = 22) and 39. 47 mg / g( n = 21),respectively. The values of PCA were 0. 4435( n = 23)for the samples from Sichuan,0. 0122( n = 22) for the samples from Zhejiang and- 4. 9850( n = 21) for the samples from Anhui. The content of paeoniflorin in biennial,triennial,four-year,five-year and six-year old Paeonia lactiflora roots were 24. 76( n = 2),37. 17( n= 16),37. 83( n = 23),39. 71( n = 16) and 37. 45 mg / g( n = 7),respectively. Conclusion: The developed method can accurately quantify the content of principal bioactive compounds in Paeonia lactiflora roots. The quality is various among Paeonia lactiflora roots cultivated in Sichuan, Zhejiang and Anhui on the basis of paeoniflorin content or the value of PCA,but the quality of Paeonia lactiflora roots cultivated in Sichuan is the best. Moreover, it is suggested Paeonia lactiflora roots should be harvested in third or fourth year based on the output and quality.

[Assay of Tetramethylpyrazine in Szechwan Lovage Rhizome and Cnidium Rhizome by HPLC-DAD-MS].

OBJECTIVE: To quantity the amount of tetramethylpyrazine in Szechwan Lovage Rhizome (Chuanxiong, the rhizome of Ligusticum chuanxiong Hort., CX) and Cnidium Rhizome(Japanese Chuanxiong, the rhizome of Cnidium officinale Makino, JCX) for quality assessment. METHODS: An HPLC-DAD-MS technique was employed to detect tetramethylpyrazine in 27 CX and 10 JCX samples. Tetramethylpyrazine was separated on a Waters Symmetry C,, column (250 mm x 4. 6 mm, 5 µm). The mobile phase was methanol-acetonitrile-water(27: 1: 72) at a flow rate of 1. 0 mL/min. The column temperature was 35 °C. DAD detection wavelength was 280 nm, while electrospray ionization detector was set at positive mode to collect MS spectrum. RESULTS: In the total of 37 herb samples, 11 samples were found to contain tetramethylpyrazine with the mean amount of 2. 19 µg/g(n = 11). 6 of 27 CX samples and 5 of 10 JCX sample were found the existence of tetramethylpyrazine with the amount of 0. 60 - 11. 75 µg and 0. 61 - 3. 05 µg/g,respectively. The correlation was not found between tetramethylpyrazine and the cultivation area, morphological character, processing or storage method for CX and JCX samples. It was possible that tetramethylpyrazine resulted from the microbes in soil. CONCLUSION: The developed method is accurate to quantify tetramethylpyrazine in CX and JCX herbs. Both the two herbs indeed contain tetramethylpyrazine, but it is not suitable to be a chemical marker to assess the quality of CX and JCX owing to low content.

[Analysis of different parts and tissues of Panax Notoginseng by Fourier transform infrared spectroscopy].

The techniques of Fourier transform infrared (FTIR) spectroscopy were applied to analyze the different parts and tissues of Panax Notoginseng (Sanqi, SQ), i.e. rhizome, main root, rootlet, fibrous root, xylem, cambium, phloem and epidermis. Both the FTIR spectra and second derivative spectra of these various parts and tissues of SQ samples were found to be similar. Their dominant component is starch resulting from the characteristic peaks of starch observed at 3 400, 2 930, 1 645, 1 155, 1,080 and 1,020 cm(-1) on the spectra of all these SQ samples. However, the varieties of peaks were found on the spectra among these specific samples. The rhizome contains more saponins than others on the basis of the largest ratio of the peak intensity at 1,077 cm(-1) to that at 1,152 cm(-1). The peaks located at 1 317 and 780 cm(-1) on the FTIR spectra of the rhizome and its epidermis indicate that the two parts of SQ samples contain large amount of calcium oxalate, and its content in the latter is relative larger than that in former. The fibrous root contains much amount of nitrate owing to the obvious characteristic peaks at 1 384 and 831 cm(-1). For the difference among the various tissues of SQ samples, the peaks at 2,926, 2,854 and 1,740 cm(-1) on the FTIR spectra of epidermis is the strongest among the various tissues of main root indicating the largest amount of esters in epidermis. Protein was also found in the cambium of the main root based on the relative strong peaks of amide I and II band at 1,641 and 1,541 cm(-1), respectively. The results indicate that FTIR spectra with its second derivative spectra can show the characteristic of the various parts and tissues of SQ samples in both the holistic chemical constituents and specific chemical components, including organic macromolecule compounds and small inorganic molecule compounds. FTIR spectroscopy is a useful analytical method for the genuine and rapid identification and quality assessment of SQ samples.

Single and combined effects of estrone and 17ß-estradiol on male goldfish.

OBJECTIVE: To assess the single and combined effects of estrone (E1) and 17ß-estradiol (E2) on goldfish (Carassius auratus). METHODS: Batch tests were conducted. Serum levels of vitellogenin (VTG) and E2, gonadosomatic indices (GSI), gonadal DNA damage and liver 7-ethoxyresorufin-O-deethylase (EROD) activity were measured after exposure for 14 days. RESULTS: The VTG level increased significantly in a concentration-dependent manner. The serum E2 level was significantly higher and the GSI level was significantly lower in goldfish after exposed to the 3 drugs. DNA damage occurred in treated samples and EROD activity was significantly suppressed 7 days after exposure. The joint effect of E1 and E2 was additive with regard to VTG induction. CONCLUSION: The results of our study highlight a series of effects of steroidal estrogens on goldfish. Further study is needed to confirm their effect as a whole.

Effects of selected metal oxide nanoparticles on multiple biomarkers in Carassius auratus.

OBJECTIVE: To study the biological effects of nanoscale copper oxide (nCuO), zinc oxide (nZnO), cerium dioxide (nCeO2) and their mixtures on Carassius auratus. METHODS: Juvenile fish (Carassius auratus) were exposed to aqueous suspensions of nCuO, nZnO, and nCeO2 (alone and in mixtures) at concentrations of 20, 40, 80, 160, and 320 mg/L. The biomarkers-acetylcholinesterase (AChE) in brain, sodium/potassium-activated ATPase (Na+/K+-ATPase) in gill, and superoxide dismutase (SOD) and catalase (CAT) in liver-were determined after 4 days of exposure. Integrated biomarker response (IBR) was calculated by combining multiple biomarkers into a single value. RESULTS: AChE and SOD activities were significantly inhibited by all test metal oxide nanoparticles (NPs) at high concentrations (⋝160 mg/L) with the exception of nCeO2. Na+/K+-ATPase induction exhibited bell-shaped concentration-response curves. CAT activity was significantly inhibited at concentrations equal to or higher than 160 mg/L. The order of IBR values was nCeO2 ≈ nZnO/nCeO2 ≈ nCuO/nCeO2 < nCuO/nZnO/nCeO2 < nZnO < nCuO < nCuO/nZnO. The joint effect seemed to be synergistic for nCuO/nZnO mixtures, additive for the ternary mixture and less than additive or antagonistic for the binary mixtures containing nCeO2. CONCLUSION: Concentration-dependent changes of enzymatic activities (AChE, Na+/K+-ATPase, SOD, and CAT) were observed in fish exposed to nanoscale metal oxides. IBR analysis allowed good discrimination between the different exposures and might be a useful tool for the quantification of integrated negative effects induced by NPs toward fish.

[Chemical change of chuanxiong raw materials during storage].

OBJECTIVE: To evaluate the chemical changes in Chuanxiong raw material (CX), the rhizome of Ligusticum chuanxiong Hort., during CX storage and further assess its quality variety. METHODS: Four CX samples were sealed and stored at ambient temperature in room for two years. These samples were quantified on the amounts of characteristic chemical compounds by HPLC-DAD-(APCI) MS techniques. RESULTS: Eight characteristic peaks in HPLC fingerprint were found to be good separation and assigned as vanillin (1), ferulic acid (2), senkyunolide I (3), senkyunolide H (4), coniferyl ferulate (5), senkyunolide A (6), Z-ligustilide (7) and levistolide A(8), respectively based on their on-line APCI-MS data and UV spectra. After CX being stored, compounds 1 - 4, and 8 were decreased by 44.4%, 52.1%, 37.6%, 52.8% and 47.5% (n = 4), respectively, whilst compounds 5 - 7 were increased by 59.1%, 40.1% and 47.5% (n = 4), respectively. CONCLUSION: Multiple chemical compounds are found to be changed during CX storage, which results in the variety of quality and therapeutic effect because most of the tested compounds have been demonstrated to be bioactive by pharmacological study and clinical trials. It is suggested that CX should be stored under dark, cool and dry condition.

The peripheral messenger RNA expression of glycogen synthase kinase-3ß genes in Alzheimer's disease patients: a preliminary study.

OBJECTIVE: To explore the peripheral leucocytic messenger RNA (mRNA) expression of glycogen synthase kinase-3ß (GSK-3ß) gene in Alzheimer's disease (AD) patients. METHODS: Using TaqMan relative quantitative real-time polymerase chain reaction, we analyzed leucocytic gene expression of GSK-3ß in 48 AD patients and 49 healthy controls. Clinical data of AD patients were also collected. RESULTS: The mRNA expression level of the GSK-3ß gene was significantly higher in the AD group (3.13±0.62) than in the normal group (2.77±0.77). Correlational analyses showed that the mRNA expression level of GSK-3ß gene in AD patients was associated with the age of onset (P=0.047), age (P=0.055), and Behavioral Pathology in Alzheimer's Disease Rating Scale total score (P=0.062) and subscores: aggressiveness score (P=0.073) and anxieties and phobias score (P=0.067). Through multivariate regression model, older age, higher anxieties and phobias score and aggressiveness score were associated with higher mRNA expression level of GSK-3ß gene. CONCLUSION: In AD patients, the mRNA expression level of the GSK-3ß gene is increased and may be related to age and behavioural pathology in AD.

[Effects of Two PPCPs on Nitrification in Sediments in the Yarlung Zangbo River].

To understand the effects of pharmaceuticals and personal care products (PPCPs) on nitrogen transformation in high-altitude rivers, we investigated the influence of the single and combined exposure of sulfamethoxazole (SMX) and 2-ethylhexyl-4-methoxycinnamate (EHMC) at different concentrations (0.01, 0.1, 1.0, 10, and 100 µg·L-1) on nitrification in the sediments of the Yarlung Zangbo River in sediment slurry experiments. All treatments significantly reduced nitrification rates, and the maximum inhibition rates induced by SMX and EHMC (alone and in combination) were 47%, 50%, and 66%, respectively. SMX significantly inhibited ammonia monooxygenase (AMO) activity in a concentration-dependent manner, with the inhibition rates ranging from 51% to 78%. The inhibitory effect of SMX combined with EHMC on AMO activity was similar to or stronger than that of SMX alone, and the inhibition rates ranged from 55% to 84%. All EHMC exposures also significantly inhibited AMO activity, but the inhibition rates decreased with an increase in EHMC concentrations. The amoA gene abundance was significantly reduced in all the treatments, and SMX alone and in combination with EHMC induced stronger inhibitory effects than EHMC alone. SMX alone and in combination with EHMC significantly inhibited HAO activity, showing a similar concentration-effect relationship, but their combined exposure produced a stronger effect. SMX alone and in combination with EHMC also significantly decreased hao gene abundance in the sediments, and the maximum inhibition rates were 76% and 68%, respectively. Although exposure to higher concentrations of EHMC increased hao gene abundance and HAO activity, the notable decrease in nitrification rates in the sediments suggested that oxidation of ammonia to hydroxylamine catalyzed by AMO was the rate-limiting step in the nitrification process. The results also showed that PPCPs influence the activities of nitrifying communities in the sediments of high-altitude rivers and inhibit nitrification, and their coexistence further increases the pressure of nitrogen loading in aquatic ecosystems.

[Effects of Roxithromycin on Reproduction,Growth, and Anti-oxidation System of Daphnia magna].

Roxithromycin (ROX) is widespread in the water environment and has been reported to have ecotoxicological effects on aquatic organisms. To improve our understanding of these effects, we selected Daphnia magna as a test organism to study acute and chronic ROX toxicity on reproduction, growth, and antioxidant systems. The acute ROX toxicity was low, with 48 h-LC50 and 96h-LC50ROX values of 60.26 mg·L-1 and 39.81 mg·L-1, respectively. Furthermore, ROX concentrations of 0.5 µg·L-1 and 50 µg·L-1 significantly increased the frequency of egg laying, total number of eggs, and number of eggs per fetus. In the early exposure stages, ROX altered the sexual maturation time of Daphnia magna, affecting the frequency of egg laying and the number of eggs per fetus to cope with environmental stress. The intrinsic growth rate was also significantly increased by 50 µg·L-1 ROX. In both treatment groups, Daphnia magna had a shorter body length, abnormal heart rate, and inhibited swimming activity. Moreover, 50 µg·L-1 ROX inhibited the activities of POD, CAT, and GSH-Px by approximately 50% and induced MDA by more than 100%, resulting in the accumulation of reactive oxygen species in the body, which could potentially damage the cell membrane. In the 50 µg·L-1 ROX treatment, per 06 was up-regulated, enhancing the immune response of Daphnia magna. In contrast. gst and gst-theta were down-regulated, suggesting that ROX could weaken the detoxification effect of Daphnia magna. jhe, ecra, ecrb, rxr, vg1, vg2, and vit-2 were also down-regulated. ROX affected the secretion of juvenile and thyroid hormones, inhibiting the synthesis of vitellogenin. Finally, ROX also affected the growth and disturbed the population stability of Daphnia magna. This study provides a reference for the effects of ROX on the reproduction and growth of aquatic organisms and their responses at protein and gene levels.

[Distribution and Ecological Risk Assessment of PPCPs in Drinking Water Sources of Henan Province].

The occurrence of emerging pollutants pharmaceuticals and personal care products (PPCPs) in aquatic environments has potential adverse effects on aquatic organisms, and the presence of PPCPs in drinking water sources is very likely to cause harm to human health. The PPCPs pollution in five typical drinking water sources in Henan province was investigated. Moreover, the source of pollutants was analyzed and the relevant ecological risks were evaluated. The results showed that the cumulative concentrations of 20 PPCPs at different sampling sites ranged from 24.2 to 317.6 ng·L-1. Caffeine (CFI) was the highest level contaminant, with the concentration up to 186.4 ng·L-1, followed by sulfamethoxazole (SMX) and ofloxacin (OFC), with detected concentrations up to 70.8 ng·L-1 and 24.2 ng·L-1, respectively. The pollution of PPCPs in Heigangkou drinking water sources was higher than those of other drinking water sources. The comparation of the labile indicator CFI and the conservative indicator carbamazepine (CBZ) concentrations implies that the pollutions from the upstream water and around scattered domestic sewage might be responsible for the PPCPs present in these drinking water sources. The risk quotient (RQ) calculation results indicated that the detected PPCPs in 5 drinking water sources have moderate to high risks to algae, while low to moderate risks to invertebrates and fish. Therefore, attention should be paid to relevant pollution control.

Gastrodia elata blume ameliorates circadian rhythm disorder-induced mice memory impairment.

Circadian rhythm disorder (CRD) in space flight can lead to memory impairment, performance decrements and adverse health outcomes, the main manifestations of which are circadian desynchronization, sleep loss and insomnia. Sleep deprivation (SD) provide the means to evaluate these effects and the risks associated with CRD on ground. Gastrodia elata Blume (GEB) has beneficial effects on the treatment of sleep disturbances and memory loss. Fresh GEB (FG), an unprocessed raw tuber of GEB, has been used as functional health food in Asian countries for a long time. However, the research report of FG to ameliorate memory impairment caused by insomnia or lack of sleep is meager. In this study, ICR male mice were sleep-deprived continuously and water extract of FG (WFG) was orally administrated (3 and 9 g/kg/d, i.g) during the SD process lasted for 25 days, except control and model groups gavage administration with water, positive control group with modafinil (MOD, 0.1 g/kg/d, i.g). We studied the effect of WFG on CRD-induced learning and memory impairment using a set of behavioral analyses including the object location recognition test (OLRT), novel object recognition test (NORT), and the passive avoidance test (PAT). In addition, oxidative stress parameters were assessed by measuring the malondialdehyde (MDA) and superoxide dismutase (SOD) reactivity in serum and hippocampus. Our results revealed that SD decreased discrimination index (DI) in OLRT and NORT, with shorter latency into the dark chamber in PAT. Both WFG and MOD treatment can reverse these changes (P < 0.05). We concluded that WFG treatment improve CRD-induced learning and memory impairment and oxidative stress damage which makes FG a promising candidate as herbal health product of memory decline in CRD.

[Occurrence and Ecological Risk of Eight Typical PhACs in Surface Water and Its Impact on Daphnia magna].

The occurrence and risk assessment of eight typical pharmaceutical active compounds (PhACs) in a receiving water body of wastewater treatment plant effluent were investigated. The results showed that the total concentrations of eight PhACs in summer and winter ranged from 27.6 to 226.4 ng·L-1 and 56.6 to 368.8 ng·L-1, respectively. The concentration of caffeine (16.2-125.8 ng·L-1) was highest, followed by roxithromycin (3.3-89.2 ng·L-1) and ibuprofen (3.6-59.2 ng·L-1). The total ecological risks (mixture risk quotients, MRQ) of eight PhACs to green algae, daphnia, and fish were 1.51, 0.08, and 5.68 in summer and 8.34, 0.22, and 6.45 in winter, respectively. The contribution rates of ketoconazole, erythromycin, and ibuprofen exceeded 49%, 85%, and 92% for MRQ in green algae, daphnia, and fish, respectively. In terms of sensitive species, green algae and fish are the most sensitive to PhACs in winter and summer, respectively. The results of 21 d chronic toxicity showed that mixed PhACs effect normal development and reproduction of Daphnia magna, resulting in an increase in reproductive capacity and swimming activity, and a reduction in heart rate and thoracic limb activity.

[Structural Characteristics of Microbial Communities in the Sediments of the Niyang River in Tibet].

The Niyang River is an important tributary of the Yarlong Zangbo River, which is also an important water source in the Gongbujiangda and Linzhi areas of Tibet. In this study, water and sediment samples from 18 sites in the Niyang River were collected. The physical and chemical properties, concentrations of 12 heavy metals, and the microbial community in the sediments were determined. The microbial community structures in the sediments collected in 2017 and 2018 were highly similar at the phylum and genus levels. The most dominant type of bacteria in the sediment of the Niyang River was Proteobacteria. Other dominant bacteria included Bacteroidetes, Acidbacteria, and Actinobacteria. At the genus level, the abundance of Flavobacterium was high. Other conditional pathogenic bacteria, such as Aeromonas and Acinetobacter, were detected. Cluster analysis found that there were certain spatial differences among the upstream, midstream, and downstream microbial communities. The microbial community of sediments in the power station reservoir area was unique. Correlation analysis showed that the temperature, dissolved oxygen, electrical conductance, Cr, Zn, Sr, and Ba in the sediments had high correlation with abundance of specific microbes at the phylum level. Redundancy analysis suggested that total nitrogen, total phosphorus, dissolved oxygen, Cr, Sr, Ba, and Mn were the main influencing factors of microbial community structure in the sediments of the Niyang River. The results of this study provide data support for understanding the spatial and temporal distribution of the microbial community in sediments of the Niyang River and identifying their environmental impact factors.

Improved chromatographic fingerprints for facile differentiation of two Ganoderma spp.

This paper addresses a comprehensive and comparative study of six phytochemical extraction methods for triterpenes from the fruiting body of Ganoderma spp. Quantitative analysis of extracts was performed by HPLC with photodiode array detection. In general, pressurized liquid extraction and microwave-assisted extraction under optimized conditions produce better yields, and the former also significantly reduces the total time of extraction and manipulation of a sample, as well as the amount of solvent used in comparison with conventional soxhlet, reflux, ultrasonic, and methanol-CO(2) supercritical fluid extractions. Based on the improved extraction protocol, the fingerprinting profiles for two species of Lingzhi were established using the consistent chromatographic features of 12 authentic samples. Eleven common peaks of ganoderic/ganoderenic acids were identified using LC-ESI-MS-MS. These specific triterpene groups were adopted as chemical markers for Lingzhi. Using chemometric analysis, the developed fingerprinting was successfully applied to differentiate between the two species under the Ganoderma genus and is applicable as a method for quality evaluation of this valuable medicinal fungus and its related proprietary products.

Biodegradation of complex bacteria on phenolic derivatives in river water.

OBJECTIVE: To isolate, incubate, and identify 4-chlorophenol-degrading complex bacteria, determine the tolerance of these bacteria to phenolic derivatives and study their synergetic metabolism as well as the aboriginal micrpbes and co-metabolic degradation of mixed chlorophenols in river water. METHODS: Microbial community of complex bacteria was identified by plate culture observation techniques and Gram stain method. Bacterial growth inhibition test was used to determine the tolerance of complex bacteria to toxicants. Biodegradability of phenolic derivatives was determined by adding 4-chlorophenol-degrading bacteria in river water. RESULTS: The complex bacteria were identified as Mycopiana, Alcaligenes, Pseudomonas, and Flavobacterium. The domesticated complex bacteria were more tolerant to phenolic derivatives than the aboriginal bacteria from Qinhuai River. The biodegradability of chlorophenols, dihydroxybenzenes and nitrophenols under various aquatic conditions was determined and compared. The complex bacteria exhibited a higher metabolic efficiency on chemicals than the aboriginal microbes, and the final removal rate of phenolic derivatives was increased at least by 55% when the complex bacteria were added into river water. The metabolic relationship between dominant mixed bacteria and river bacteria was studied. CONCLUSION: The complex bacteria domesticated by 4-chlorophenol can grow and be metabolized to take other chlorophenols, dihydroxybenzenes and nitrophenols as the sole carbon and energy source. There is a synergetic metabolism of most compounds between the aboriginal microbes in river water and the domesticated complex bacteria. 4-chlorophenol-degrading bacteria can co-metabolize various chlorophenols in river water.

[Distribution and Environmental Risk of Pharmaceutically Active Compounds in the Traditionally Aqueous Phase of Effluent-receiving Rivers].

Colloid media are not only an important "sink" for pollutants in the aquatic environment, but also a crucial regulating unit for the biogeochemical cycle of pollutants. In this study, the distribution and environmental risk levels of ten typical pharmaceutically active compounds (PhACs) in the water phase of effluent-receiving rivers were investigated using cross-flow ultrafiltration, solid-phase extraction, and liquid chromatography-tandem mass spectrometry as the pretreatment and analysis methods. The results showed that the total concentrations of the ten PhACs in the dissolved phase and colloidal phase ranged from 27.2 to 168.1 ng·L-1 and 164.5 to 751.1 ng·g-1, respectively. Ibuprofen (IPF), roxithromycin (ROX), and erythromycin (ETM) are the dominating pollutants in the dissolved phase and colloidal phase, accounting for more than 80% of the total concentration. Strong adsorption properties for ROX, ketoconazole, ETM, and sertraline were found in the colloid phase, their colloid/water distribution coefficients (lgKcol) ranged from 3.2 to 4.0, and the percentage of PhACs absorbed to the colloidal phase reached 21.1%-34.5%. The risk assessment of acute and chronic toxicity to algae, daphnia, and fish showed that only IPF presented a high chronic risk to fish, while the risk levels of the other PhACs were at or below medium risk. It is worth noting that, in comparison with their acute risk, most PhACs have chronic negative effects on higher aquatic organisms.

Prediction of toxicity of phenols and anilines to algae by quantitative structure-activity relationship.

OBJECTIVE: To measure the toxicity of phenol, aniline, and their derivatives to algae and to assess, model, and predict the toxicity using quantitative structure-activity relationship (QSAR) method. METHODS: Oxygen production was used as the response endpoint for assessing the toxic effects of chemicals on algal photosynthesis. The energy of the lowest unoccupied molecular orbital (E(LUMO)) and the energy of the highest occupied molecular orbital (E(HOMO)) were obtained from the ChemOffice 2004 program using the quantum chemical method MOPAC, and the frontier orbital energy gap (deltaE) was obtained. RESULTS: The compounds exhibited a reasonably wide range of algal toxicity. The most toxic compound was alpha-naphthol, whereas the least toxic one was aniline. A two-descriptor model was derived from the algal toxicity and structural parameters: log1/EC50 = 0.268,logKow - 1.006deltaE + 11.769 (n = 20, r2 = 0.946). This model was stable and satisfactory for predicting toxicity. CONCLUSION Phenol, aniline, and their derivatives are polar narcotics. Their toxicity is greater than estimated by hydrophobicity only, and addition of the frontier orbital energy gap deltaE can significantly improve the prediction of logKow-dependent models.

Biodegradability of chlorinated anilines in waters.

OBJECTIVE: To identify the bacteria tolerating chlorinated anilines and to study the biodegradability of o-chloroaniline and its coexistent compounds. METHODS: Microbial community of complex bacteria was identified by plate culture observation techniques and Gram stain method. Bacterial growth inhibition test was used to determine t he tolerance of complex bacteria to toxicant. Biodegradability of chlorinated anilines was determined using domesticated complex bacteria as an inoculum by shaking-flask test. RESULTS: The complex bacteria were identified, consisting of Xanthomonas, Bacillus alcaligenes, Acinetobacter Pseudomonas, and Actinomycetaceae nocardia. The obtained complex bacteria were more tolerant to o-chloroaniline than mixture bacteria in natural river waters. The effects of exposure concentration and inoculum size on the biodegradability of o-chloroaniline were analyzed, and the biodegradation characteristics of single o-chloroaniline and 2, 4-dichloroaniline were compared with the coexistent compounds. CONCLUSION: The biodegradation rates can be improved by decreasing concentration of compounds and increasing inoculum size of complex bacteria. When o-chloroaniline coexists with aniline, the latter is biodegraded prior to the former, and as a consequence the metabolic efficiency of o-chloroaniline is improved with the increase of aniline concentration. Meanwhile, when o-chloroaniline coexists with 2,4-dichloroaniline, the metabolic efficiency of 2,4-dichloroaniline is markedly improved.

QSARS for acute toxicity of halogenated benzenes to bacteria in natural waters.

OBJECTIVE: To measure the acute toxicity of halogenated benzenes to bacteria in natural waters and to study quantitative relationships between the structure and activity of chemicals. METHODS: The concentration values causing 50% inhibition of bacteria growth (24h-IC50) were determined according to the bacterial growth inhibition test method. The energy of the lowest unoccupied molecular orbital and the net charge of carbon atom of 20 halogenated benzenes were calculated by the quantum chemical MOPAC program. RESULTS: The log1/IC50 values ranged from 4.79 for 2,4-dinitrochlorobenzene to 3.65 for chlorobenzene. A quantitative structure-activity relationship model was derived from the toxicity and structural parameters: log1/IC50 = -0.531(E(LUMO)) + 1.693(Qc) + 0.163(logP) + 3.375. This equation was found to fit well (r2 = 0.860, s = 0.106), and the average percentage error was only 1.98%. CONCLUSION: Halogenated benzenes and alkyl halogenated benzenes are non-polar narcotics, and have hydrophobicity-dependent toxicity. The halogenated phenols and anilines exhibit a higher toxic potency than their hydrophobicity, whereas 2,4-dinitrochlorobenzene is electrophile with the halogen acting as the leaving group.

Assay of free ferulic acid and total ferulic acid for quality assessment of Angelica sinensis.

Activity of Chinese Danggui (DG), the processed root of Angelica sinensis (Oliv.) Diels, is linked to the ferulic acid content but the stability of ferulic acid during extraction for medicinal use is not known. The stabilities of ferulic acid and coniferyl ferulate were evaluated in the extracts of DG using a variety of extraction solvents. These included various combinations and proportions of methanol, water, formic acid, 1 M aqueous hydrochloric acid and 2% sodium hydrogen carbonate (NaHCO3) in water. Coniferyl ferulate was found liable to hydrolyze into ferulic acid in neutral, strongly acidic and basic solvents, where heat and water could facilitate this hydrolysis. However, the hydrolysis was relatively resisted in weakly organic acid. Based on the stability evaluation, two new terms, namely: free ferulic acid and total ferulic acid, were suggested and defined. Free ferulic acid refers to the natural content of ferulic acid in herbs. Total ferulic acid means the sum of free ferulic acid plus the amount of related hydrolyzed components. Meanwhile, the high-performance liquid chromatographic (HPLC) method was developed to assay free ferulic acid and total ferulic acid in DG using methanol-formic acid (95:5) and methanol-2% NaHCO3 in water (95:5) as extraction solvents, respectively. Ten DG samples were investigated on their contents of free and total ferulic acid. The results indicated that the amount variety of free ferulic acid was larger than that of their counterparts, and the ratio of total ferulic acid to free ferulic acid was 4.07 +/- 2.73 (mean +/- SD, n = 10). The chemical assay of DG using total ferulic acid content would be a better choice to assess the herbal quality and was recommended.